UTC Adoption

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UTC Adoption

Victor Engel
Dear Calendar People,

Yesterday, I watched "Hidden Figures". In the movie, around 1961, they were replaying the launch of a space module prior to launching John Glenn, which was in 1962. The times indicated were in UTC. I thought UTC wasn't adopted until later. DId NASA adopt UTC this early?

Victor
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Re: UTC Adoption

Jim Riley-4
On Fri, 13 Jan 2017 11:15:58 -0600, Victor Engel <[hidden email]>
wrote:

>Yesterday, I watched "Hidden Figures". In the movie, around 1961, they were
>replaying the launch of a space module prior to launching John Glenn, which
>was in 1962. The times indicated were in UTC. I thought UTC wasn't adopted
>until later. DId NASA adopt UTC this early?

This indicates that the US and UK had agreed to coordinate their time
measurement in 1959, with implementation in 1960. The term "Universal
Time" was proposed in 1928.

http://www.bipm.org/cc/CCTF/Allowed/18/CCTF_09-32_noteUTC.pdf

Given the origins of the US space program, those involved would be
familiar with Zulu Time, and also recognize the need for
location-independent timing (low earth-orbit satellites in
west-to-east orbits are advancing about 15 seconds local time per
second.
--
Jim Riley
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Re: UTC Adoption

Victor Engel
In the movie, they said, "U T C". I recall hearing time announcements on the radio as "Coordinated Universal Time". I guess my question is whether the engineers at NASA would have used "U T C" when announcing during/in preparation for a launch.

On Fri, Jan 13, 2017 at 12:16 PM, Jim Riley <[hidden email]> wrote:
On Fri, 13 Jan 2017 11:15:58 -0600, Victor Engel <[hidden email]>
wrote:

>Yesterday, I watched "Hidden Figures". In the movie, around 1961, they were
>replaying the launch of a space module prior to launching John Glenn, which
>was in 1962. The times indicated were in UTC. I thought UTC wasn't adopted
>until later. DId NASA adopt UTC this early?

This indicates that the US and UK had agreed to coordinate their time
measurement in 1959, with implementation in 1960. The term "Universal
Time" was proposed in 1928.

http://www.bipm.org/cc/CCTF/Allowed/18/CCTF_09-32_noteUTC.pdf

Given the origins of the US space program, those involved would be
familiar with Zulu Time, and also recognize the need for
location-independent timing (low earth-orbit satellites in
west-to-east orbits are advancing about 15 seconds local time per
second.
--
Jim Riley

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Re: UTC Adoption

Jim Riley-4
It appears that the history of the terminology has been obscured by
the more recent discussion about eliminating leap seconds, so what I
could find is what happened up through 2000, rather than concentrating
on the specifics of the 1960s.

Universal Time (UT) had been understood as a concept since the
beginning of the 20th Century. UT is the same as GMT. When variations
in the rotational speed of the earth were recognized, they were
informally designated as UT0, UT1, and UT2.

The initial problem was that radio-transmitted time signals from
different countries were not synchronized. The US and UK agreed to
coordinate their radio signals which was implement from January 1,
1960. UTC was an approximation of UT2, and later UT1, that uses a
fixed length second, made possible by development of atomic clocks in
the mid-1950s, which is more reliable and consistent than the rotating
earth.

It makes more sense to implement something as a proof of concept
rather than promlugate a standard then implement it. Since the US and
UK were English-speaking they would naturally use UTx, and since it
was an engineering problem, may have been more casual about
terminology than a scientist, lawyer, or linguist would.

This publication notes that the UK and US had begun "coordinating"
their time and frequencing transmissions early in 1960 (I've seen
elsewhere it was January 1, 1960).

http://nvlpubs.nist.gov/nistpubs/Legacy/MP/nbsmiscellaneouspub236.pdf

While this says that WWV was broadcasting UT, it was broadcasting an
approximation of UT.

It appears that the first official adoption as a standard was

Recommendation 374 (or 374-1) of CCIR (1963). CCIR is the predecessor
of the ITU-R. I have not come across the text of Recommendation 374.

If it was recommended that national time services follow a certain
practice, then the practice must already have been implemented in some
places (at minimum the the US and UK).

http://geodesy.unr.edu/hanspeterplag/library/geodesy/time/met5_3_S02.pdf

This suggest that initial coordination was simplified with only the US
and UK involved.

It is possible that "UTC" preceded "Coordinated Universal Time (UTC)"
and "Temps universel coordonné (UTC)"

This is a transcript of communication with Friendship 7. It annotates
in flight time.

https://library.osu.edu/projects/friendship-7/flight_radio.html

At about 0:10:45 into this video, there is a transmission that says
the countdown had been restarted at 14:41 Zulu following a hold at
-6:15. Given the subject matter of the film, was "Zulu" considered
offensive?

https://www.youtube.com/watch?v=yz9-KmSStKs

At about 0:02:00 this shows flight control, with the first clock
showing Standard Time (presumably EST). The second clock is "Countdown
Clock". It is conceivably UTC/Z/GMT, but the minute hands of the two
are not in sync. Or it may actually be set up to read 0:00:00
(12:00:00) at launch.

BTW, the above is an excellent watch, plus it has subtle bits of
propaganda.

https://www.youtube.com/watch?v=3o-U1Jo78P8

https://www.youtube.com/watch?v=yz9-KmSStKs
http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1978QJRAS..19..290S

http://www.ucolick.org/~sla/leapsecs/timescales.html

http://www.ucolick.org/~sla/navyls/0943.html

http://www.ucolick.org/~sla/navyls/0336.html

https://sizes.com/time/time_universal.htm

https://itunews.itu.int/En/4271-What-is-in-a-nameBROn-the-term-Coordinated-Universal-Time.note.aspx

https://www.cl.cam.ac.uk/~mgk25/time/metrologia-leapsecond.pdf

http://www.iau.org/static/resolutions/IAU1976_French.pdf

On Fri, 13 Jan 2017 12:37:52 -0600, Victor Engel <[hidden email]>
wrote:

>In the movie, they said, "U T C". I recall hearing time announcements on
>the radio as "Coordinated Universal Time". I guess my question is whether
>the engineers at NASA would have used "U T C" when announcing during/in
>preparation for a launch.
>
>On Fri, Jan 13, 2017 at 12:16 PM, Jim Riley <[hidden email]> wrote:
>
>> On Fri, 13 Jan 2017 11:15:58 -0600, Victor Engel <[hidden email]>
>> wrote:
>>
>> >Yesterday, I watched "Hidden Figures". In the movie, around 1961, they
>> were
>> >replaying the launch of a space module prior to launching John Glenn,
>> which
>> >was in 1962. The times indicated were in UTC. I thought UTC wasn't adopted
>> >until later. DId NASA adopt UTC this early?
>>
>> This indicates that the US and UK had agreed to coordinate their time
>> measurement in 1959, with implementation in 1960. The term "Universal
>> Time" was proposed in 1928.
>>
>> http://www.bipm.org/cc/CCTF/Allowed/18/CCTF_09-32_noteUTC.pdf
>>
>> Given the origins of the US space program, those involved would be
>> familiar with Zulu Time, and also recognize the need for
>> location-independent timing (low earth-orbit satellites in
>> west-to-east orbits are advancing about 15 seconds local time per
>> second.
>> --
>> Jim Riley
>>
--
Jim Riley
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Re: UTC Adoption

RobinAdams
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In reply to this post by Victor Engel
"Hidden Figures" is a great movie and the reconstructions were meticulous but I don't think they got it right with using the term UTC. It was not in use until years later and I think NASA would have used the term ZULU in the early 60s. There was some resistance to changing to UTC in many organizations. In the late 60s international radio broadcasters adopted it with the exception of the BBC still refers to GMT and the international TV feeding systems also still uses GMT.
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